1979-1985 Turbo Riviera Questions

[Guest]

How reliable is the 3.8 turbo in these cars?

[BUICK RACER]

Very reliable if they were maintained with oil changes at frequent intervals, like every 3000 miles if driven short distances or every 7500 if driven long distances. The 3.8 and 3800 are one of the best engines every produced by GM, if not the best, receiving awards for years. There are multitudes of them running over 250,000 miles with little repair needed, oil changes are the biggest thing, that makes them survive! The turbos in the Riv's are different than the Grand Nationals, as the turbo Riv's were carb engines where the GN's were fuel injected, the Riv turbo is an older technology than the GN. Same principles hold true change the oil at correct intervals and the engine should last longer than the car! Check out this web site for some more info Before Black

[NTX5467]

When these cars were new and then aged, the main issues were more maintenance related. Just as with those vintage of 3.8L V-6 motors, regular oil changes were very important for the longevity of the crankshaft and its bearings (the middle one would usually be the first to go when the oil passages in the block would get sludged up; usually in the 80,000 mile range if they had seen so-so maintenance).

The first years of the Turbo 3.8L V-6 were some of the first GM engines to use knock sensors to control clattering. The initial calibrations usually resulted in clattering under part throttle acceleration whereas the system was better fine-tuned in later years.

As far as specific turbo-related issues, they seemed to be somewhat prone for the oil seal in the turbo to get coked up and not seal the turbine shaft with time and age. This could result in the crankcase being "vacuumed" of its oil over a period of time. Combine poor maintenance and lowering oil levels and it was not a good combination for the owner's finances.

These are some of the things we saw with the Turbo Monte Carlos back then. When the Chevy V-8s became more plentiful and the fuel issues eased up some, we seemed to ease out of the turbo business in our vehicle inventory. Plus, at that time GM seemed to have a "feature engine" for each division and the Turbo 3.8L V-6 and its non-turbo bretheren were Buick's feature engines so that's where most of the turbo production ended up as time went on.

We had another case where a Riviera came in with a failed turbo. We got a new one and put it on. It came back a few months later with another failed turbo. The car had over 100,000 miles and was sludged up. What it needed was a teardown and rebuild (which naturally would include vatting the block and getting the oil passages in it cleaned out). Deactivating the turbo is not the easiest thing to do either. We might have fixed it for a reduced rate or something and provided no shop warranty on the band-aid repair.

Later years were notably better in the knock sensor calibration and had higher horsepower ratings. Since that time, oil technology and products have improved a good bit too.

In some respects, buying a used turbo car would certainly be a situation where being an informed shopper would be advantageous--or you could possibly "expect" to have to replace the turbo as a matter of course and hope that you might not have to. Of course, the Turbo V-6 enthusiasts can guide you on where to get a rebuilt turbo instead of getting one via a GM dealer (where they are very possibly discontinued anyway). I would be especially concerned with what the engine oil dipstick looked like plus the oil filler cap's underside. That plus some assurances of the use of a high quality motor oil and filer that were changed at the 3000 mile interval or thereabouts.

You could also check the wastegate mechanism for correct operation and look for any modifications in that respect.

Other than the maintenance items I've mentioned, I think I'd try to aim for the later year models with their progressive product improvements as the first years were somewhat crude in execution, by comparison.

There are some other Buick-oriented websites that might offer some guidance in this area too.

Happy shopping!

NTX5467